The present invention relates to a new and improved method of analysing a measuring liquid in an analysis system.
More specifically, the method of the invention is of the type employing measuring devices which deliver a respective measuring value for a respective predetermined property of the measuring liquid. The measuring liquid essentially consists of a carrier liquid and a sample contained therein which is in a preparatory state, and the preparatory state constitutes one of a number or predetermined preparatory states correlated to the analysis system. At least one characteristic value of the sample is calculated in a computer from at least one of the measuring or measurement values and at least one coefficient correlated to the characteristic value and the preparatory state.
The sample is for instance a blood sample. During the examination of a blood sample it is known to measure one or more of the following characteristic values: concentration of the erythrocytes, concentration of the leucocytes, concentration of the thrombocytes, weight concentration of hemoglobin, mean volume of the erythrocytes, volume proportion of the erythrocytes in the blood sample (hemotological critical value), mean weight of the hemoglobin in an erythocyte, and possibly still other characteristic values or parameters. The sample also can consist of, for instance, other biological substances, such as urine, bile, lymph, plasma, in which there are to be determined different components such as dyes, sugar, protein and so forth as the characteristic values. It is also possible to analyse bacteria colonies, waste water samples, dust samples, in which there is to be measured the concentration of substances and/or the distribution of particles. Finally, the sample can be a placebo or a standard sample for calibration purposes.
To perform such analysis these samples are generally admixed with a carrier liquid--for instance water or isotonic plasma replacement solution--in a predetermined dilution. Depending upon the requirements, it is also possible to perform chemical or biological treatments--for instance oxidation, reduction, hemolysis and so forth--for instance fluorescence or radioactivity--by the addition of a marking substance. Such treatment of the sample, before or after its dilution in the carrier liquid, as well as the attainment of the desired solubility or suspension effect with desired dilution degree, are collectively termed the "preparation of the sample", and the state or condition in which the sample ultimately appears in the carrier liquid is designated as the "preparation or preparatory state".
Analysis systems of the previously mentioned type are known to the art, for instance, from German Pat. Nos. 1,673,146, 1,798,431, and 2,324,057. In such type analysis systems there are determined a number of characteristic values by means of a number of analysis devices. Each analysis device which is composed, among other things, of a sensor and evaluation device, is however tuned to a predetermined preparatory or preparation state, and it is not immaterial whether sample preparation has been carried out manually or, for instance, as disclosed in the aforementioned Pat. No. 1,798,431, by the device itself. Nothing is provided for an automatic determination, wherein for the purpose of calibrating this device there is analysed pure carrier liquid. Also, it is not possible to selectively employ the same analysis device for counting erythrocytes, leucocytes, or thrombocytes and thus, to save equipment costs. The analysis devices, in combination with the therewith connected computer devices, deliver false values of the characteristic values if there are employed other than the contemplated preparation states.
An analysis of the pure carrier liquid has been proposed, for instance, in the German Patent Publication No. 2,058,081. Here, in an additional analysis device there is continuously measured pure carrier liquid, in order to accommodate a coefficient used in the computation of a characteristic value to the changes in the properties of the pure carrier liquid. Notwithstanding the foregoing measures, also with this analysis system false values are produced if there are employed other preparation states than the single one which is contemplated.
Methods for determining false measuring values have been proposed, for instance, in German Pat. No. 2,116,595 and German Pat. No. 2,120,697. However, in this case one is only concerned with the determination of the faulty functioning of an analysis device. There is no correlation with the preparatory or preparation state of the sample. Moreover, the comparison of measuring values with threshold values in analysis systems is known as such. Apart from determining faulty functions such is also used for the classification of measuring values for producing a histogram, such as for instance disclosed in the published German Patent Application No. 2,418,559.
In the published German Patent Application No. 2,166,597 there has been disclosed a self-regulating determination of a characteristic value based upon the preparatory state of the sample. In this analysis system the coefficients needed for the unmistakable formation of the analysis results are automatically prepared. For this purpose there are used liquid containers provided with special coding means. A respective predetermined preparatory state corresponds to a respective code character or sign, such that the insertion of the liquid container into the analysis device sets the system to computation of a characteristic value which corresponds to the code character or sign. The analysis system is self-regulating as concerns the code sign which is carried by the liquid container, but not in respect of the liquid contained within the container. The operator must therefore make sure that, in accordance with the preparatory states, there is always used the correct liquid container. While the problem of self-regulating analysis systems was recognized in the aforementioned patent, the proposed solution cannot however be designated as self-regulating.
The self-regulation of the analysis system, as for instance proposed in the published German Patent Application No. 2,529,902, need not be limited to the selection of the suitable coefficients. Quite to the contrary, it can relate to the selection of the entire appropriate measurement and calculation program. Also in this case, the self-regulation is controlled by mechanical-optical means which are manually correlated by the operator to the liquid containers containing the samples, so that also this solution has the previously discussed drawbacks and cannot be characterized as self-accommodating or self-regulating.